When we examine the human body we see a beautiful example of effective evolutionary design. But it comes with a price. Under the surface, evolution has left indelible scars. Our bodies are littered with evolutionary trade-offs, quick fixes and compromises. And mismatches with modern environments. All this we interpret today as sickness and disease. This is your body thanks to evolution by natural selection, or, by deliberately conflating the theory with the theorist, this is your body by Darwin.

BODY BY DARWIN

The father of the science of evolutionary medicine, Randolph (Randy) Nesse, has a favorite aphorism: “Medicine without evolution is like engineering without physics.” In the same way that it would be impossible to imagine building the Rosetta spacecraft, sending it 300 million miles to rendezvous with Comet 67P, and successfully deploying the Philae lander, chock-full with sampling instruments, without physics and specifically Newtonian mechanics, it proves similarly impossible, for instance, to get to the root of the horrifying scourge of Alzheimer's disease unless we ask deep and fundamental questions, informed by evolution, about what the alleged poisonous plaques of beta-amyloid protein are doing in the brain in the first place. Is amyloid pure pathology or does it have an vital evolved function in the brain? In this sense, Nesse has frequently claimed that the value of evolution to medicine is that it while it may lead directly to changes in medical practice or indeed to new therapies, more fundamentally its value lies in explaining why things are as they are. That is why Nesse argues that evolutionary biology should be the foundation and cornerstone for medicine as it should be for all biology. This book is an attempt to put yet more flesh on the bones of Nesse’s idea that evolution is the “physics” of medicine. I describe the evolutionary background to seven areas of human disease that are causing deep contemporary medical concern to explain why they exist in the first place—why things are how they are - and how evolution might help us to combat them. I hope it will leave readers with a new respect for evolution as the prime mover for the structure and function of human bodies, even if it does, on occasions, cause them to break down and drives us into ER!

Each chapter is built around the sometimes harrowing but always inspiring personal stories of people trapped in the disease process in question. Each chapter provides an evolutionary explanation for why the disease has come about, and each chapter shows how medical researchers, using powerful insights gained from thinking about disease in an evolution-informed way, are charting our way out of it.

ABSENT FRIENDS

How a modern version of the hygiene hypothesis - called the "old friends" hypothesis - explains why the Western world is riddled with allergic and autoimmune diseases, and what we can do about it.

A FINE ROMANCE

How evolutionary theory explains why the battle between the different selfish genetic interests of mothers, fathers, and fetuses causes low fertility and can lead to diseases of pregnancy like recurrent pregnancy loss, preeclampsia and gestational diabetes.

THE DOWNSIDE OF UPRIGHT

What is the relationship between the fact that we have evolved to walk upright - our bipedalism - and a range of orthopedic illnesses?

DIY EYE

Creationists have always used the example of the "irreducible complexity" of the human eye as the bedrock of their argument that God designed the human body, not evolution. Modern developmental biology, however, not only strongly rebuts creationism but explains the astonishing secret of how the recipe for eyes actually unfolds from within the developing eye itself, not from external influences, and is leading to cures for eye diseases like retinitis pigmentosa and macular degeneration.

HOPEFUL MONSTERS

How does cancer evolve so remorselessly towards malignancy that it is proving almost impossible to cure? Cancer evolution can be so extreme and drastic it is forcing us to re-write the rules of evolution by resuscitating a heresy from the 1940s.

A PROBLEM WITH THE PLUMBING

Why are coronary arteries evolution's answer to feeding our powerful, muscular hearts with the food and oxygen they need and how has this led to the continuing pandemic of coronary heart disease?

THREE SCORE YEARS - AND THEN?

Research into curing Alzheimer's disease has become hopelessly bogged down and billions of dollars have been wasted trying to turn the "amyloid hypothesis" into therapy. Can we use evolutionary thought to better explain why dementia comes about in a way that might lead to fresh hope for a cure?

READ ON DOWN TO ENTER MY BLOG WHICH IS BASED ON THE BOOK AND EVOLUTIONARY MEDICINE IN GENERAL. COMMENTS AND RESPONSES STRONGLY INVITED!

Tuesday, 9 June 2015

Alzheimer’s origins tied to rise of human intelligence

In Body by Darwin I argue that Alzheimer's disease is a disease of neurons and synapses, not amyloid and phosphorylated tau protein. Here the researchers identify 6 genes that they have evidence were strongly selected for 50,000 and 200,000 years ago (approx.). Here's a quote from the Nature piece: "The study finds evidence that 50,000 to 200,000 years ago, natural selection drove changes in six genes involved in brain development. This may have helped to increase the connectivity of neurons, making modern humans smarter as they evolved from their hominin ancestors. But that new intellectual capacity was not without cost: the same genes are implicated in Alzheimer's disease." It seems the central idea is the metabolic cost of running hot brains finding its repercussions in AD.

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The Science Factory

OUT NOW!

BODY BY DARWIN was published in the US in October this year and in the UK and the rest of the English-speaking world, in November. Click on the book cover to link to the book's page on the University of Chicago Press website. Read the excellent blurbs!!

BODY BY DARWIN German edition

Random House in Germany have just published the cover for their version. The title - DER FLUCH UNSERER GENE - roughly translates as THE CURSE OF OUR GENES. Which is not really what the book is about - though it does come into it! A hint of "lost in translation"??

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About Me

I have spent most of my professional life inside the science documentary television industry, with evolutionary biology a subject I have visited many times. Until 1992 I was a senior producer and director for BBC Television, where I contributed many films to the BBC’s long-running flagship science series ‘Horizon’ (including two landmark programmes presented by Richard Dawkins, “Nice Guys Finish First” and “The Blind Watchmaker”). My first book, “Not a Chimp” ('A provocative book that should be read by anyone interested in the debate about similarities and differences between humans and chimpanzees', Dan Agin, Huffington Post) was published by Oxford University Press in 2009. My second book, “Body By Darwin”, to which this blog is dedicated, will be published by University of Chicago Press in November, 2015.